Adding Transmission Fluid To The Fuel Tank

I've got a 2001 Taco with about 240k miles. Ove the last year I've had major issues, which I think, I've gotten mostly fixed. However, it still misses at low RPMs and sometimes if my rpms are in the 1500-2000 range. I upgraded to to 89 octane and I've been adding Slick 50 Fuel Treatment every fill up (every week), but I have to order it from Amazon and it's expensive, about $13 a bottle.
Someone told me about adding Automatic Transmission Fluid to the fuel tank. From what I'm reading it used to be a thing back in the day. Has anyone tried this with a more modern engine?

 

It was used before the days of catalytic converters and injectors.

Do not use this.

If you want to go hard core read up on seafoam cleaning.

 

Ok. I've seem Seafoam in the stores. Is it better than the Slick 50?

 

Real hammer and anvil tech on old carburated motors was to add copius amounts of water to a fully warm running motor (this side of stalling). Worlds best steam cleaner. Pretty brutal though. There are some good additives that are less caustic. BG and Seafoam are pretty effective.

Old school fix is to add trans fluid to oil to break up carbon in stuck lifters, free stuck rings. Problem can be it works so well that a highly sludged engine can desludge/dislodge too fast and plug sensitive oil passages like vvt ect.

Engine oils are so much better now. Sludge build up is nothing like the oid parfin based cooked on oil sludge. The 70's hot egr passages plus old parfin wax oil commonly packed v8 intake valleys with cooked carbon sludge. it would fill the lifter valley so full it would leave a molded a full impresion of the intake bottom.

 

Maybe double check TPS and even PCV valve. Both caused stutters/skips for me similar to what you describe.

 

IMHO, Chevron Techron fuel system cleaner is what you want to use if you feel your fuel injection system needs assistance. I get mine at wally-world....

https://www.walmart.com/ip/Chevron-Techron-Concentrate-Plus-10-oz/16647989

 

I used BG MOA and EPR in my oil. It definitely cleared out some sludge, just make sure to follow the directions. https://amzn.to/4fMeEog

 

That's some good stuff,,, they make very good products, I really like the EPR, use it every oil change, it helped with the oil consumption

 

Marvel mystery oil can be added to the fuel tank. Follow their directions of course. I've never been a fan of putting fuel additives in the tank. Pretty sure these days the fuel we use has plenty of detergents already in it.

 

Did you check and/or replace the injectors, along with verifying valve clearances?

 

I have added ATF to the fuel in a 3.4l V6 with 240,000 mi. 2 ounces in the tank at fill up. After a 1200 mi. trip the motor was noticeably smoother at idle. Amsoil PI fuel system cleaner made a difference in cleaning the fuel system also...it made the sending unit sticky for a while maybe it loosened some gummy stuff in the tank. BG MOA seems to be good along with their cooling system additive and some of their ATF additive for the power steering.

Valvoline Restore and protect motor oil is a new product that cleans deposits slowly from the motor, and does work well.

Motor Kote additive is a friction reducer for motor oil and does work (gives a small mpg increase). There is a concern that it has a slightly corrosive ingredient like chlorine. Its hard to find good, conclusive info about this.

 

If it's the 3.4L, I had one in my old T-100 and had a problem like this when my plug wires were going bad.

 

perfectly stated
Agreed

 

ATF is a detergent

I have added to oil…drove for 3 days and then changed oil

as koco stated don’t see any catastrophic effects if added in small amounts

 

Part of me is afraid to know what getting that done would cost

 

I decarbon quit a few engines with a gallon of water and some atf poured down the carb..

Marvel mystery oil works good in the tank. It's cat and sensor safe. https://marvelmysteryoil.com/pages/faqs

 

I appreciate the feedback